Abstract

We present a novel method of calibration of crosstalk probability for multi-pixel photon counters (MPPCs) based on the measurement of the normalized second-order intensity correlation function of coherent light. The method was tested for several MPPCs, and was shown to be advantageous over the traditional calibration method based on the measurements of the dark noise statistics. The method can be applied without the need of modification for different kinds of spatially resolved single photon detectors.

Figures (3)

Experimental setup. Nd:YAG laser at 532 nm was used as a source of coherent light. The beam was attenuated by a neutral density filter (ND), and coupled into a single mode fiber (SMF). The intensity of the beam was controlled by two polarizing beamsplitters (PBS) and a half-wave plate (HWP). The beam impinged on the detector under test (MPPC), with the output connected to a data acquisition card (AD card). Calibration of the source was done in a Hanbury-Brown and Twiss (HBT) interferometer by erecting a flipping mirror (FM). The HBT consisted of a non-polarizing beamsplitter (NPBS) and two avalanche photodiodes (APD) connected to a coincidence circuit.

Dependence of crosstalk probability p + 2p2 (red squares), found from g(2) measurements, and pDC, measured from the dark noise (black circles) on temperature for MPPC with 50x50 μm2 pixel size. Solid line is a fit with a quadratic function.